In an anonymous etching of about 1690, a woman personifying reason and pointing to her forehead, indicating the seat of reason in her brain, hands the keys to the treasure-house of knowledge to Aristotle. The caption held aloft by the putti reads ‘I make distinctions [between humans] and brute animals, unlocking the sacred reason’.

Now in the Wellcome Collection, the etching articulates Aristotle’s position that one of the characteristics that distinguishes the human animal from other fauna is the ability to deliberate and use logic. Aristotle looks appropriately grateful.